Current concept of the visual pathway involves the formation of 11-cis retinol from all-trans retinyl esters by an isomerohydrolase. Both 11- cis retinal and 11-cis retinyl esters are derived from this 11-cis retinol and this branch point of the visual pathway is known. Although the fate of 11-cis retinal to serve as visual chromophore has been well studied, exactly how 11-cis retinyl esters are used to supply retinal chromophores for pigment regeneration is not known. Previous studies conducted in our laboratory established the presence of an 11-cis retinyl ester hydrolase activity in the bovine retinal pigment epithelium (RPE) microsomes. Our current research focused on the purification and biochemical characterization of this 11-cis retinyl ester hydrolase enzyme. In this faculty development project, we propose to expand the focus of our current biochemistry research to cover molecular biology. The applicant will work full-time for five consecutive summers in the laboratory of Dr. John Lee at the Department of Biochemistry at the University of Texas Health Science Center in San Antonio to clone and to sequence the gene encoding this protein. Expression of the gene encoding this enzyme will also be studied in bovine retinal pigment epithelial primary cell cultures. This research is important because an understanding of the details of this branch of the visual pathway is lacking. In addition, this faculty development program will also expand the applicant's current teaching and research focus from biochemistry to molecular biology. This is supportive of his department's new focus in the area of cellular and molecular neurobiology. This expansion of the applicant's teaching and research programs will also bring modern biology concepts and techniques to minority and non-minority students at The University of Texas at San Antonio.